Picked up a pair of PI Amfib tights at the LBS. They do not come with chamois - when I asked the salesman about this he said that people wear their usual bike shorts under the tights. Trying them on that way it seems pretty tight and stiff around the hips/groin area. I wonder if these tights are really meant to be worn with shorts under, or is there a better way to get a chamois in there? PI website gives minimal info and is no help with this. Thanks.